In a pipe arrangement for an automotive fuel supply system, a fuel hose defines a path for supplying a fuel pumped from a fuel pump, and is connected to a fuel delivery pipe. In the pipe arrangement, the fuel is pressurized to a predetermined constant pressure level in the hose by the pump for the delivery of the fuel. In a system adapted to deliver the fuel to an engine by a plurality of fuel delivery devices, pulsation (so-called fuel pressure fluctuation) is caused by one of the fuel delivery devices in the pipe arrangement, and a fuel pressure in the other fuel delivery device becomes higher or lower than a desired pressure level, so that the amount of the fuel to be injected is liable to be deviated from an intended level. Therefore, there is a demand for a fuel hose which is capable of suppressing the pulsation in the pipe arrangement. It is conceivable to use a resin hose, a rubber hose or a multi-layer hose including a resin layer and a rubber layer (see, for example, PTL 1) conventionally used as the fuel hose, but the following problems are encountered.
The resin hose has a fuel permeation resistance (fuel barrier property), but fails to suppress the pulsation because of its higher rigidity. The rubber hose is effective for suppressing the pulsation, but poorer in fuel permeation resistance (fuel barrier property). Further, the multi-layer hose including the inner resin layer and the rubber layer has difficulty in ensuring both the fuel permeation resistance (fuel barrier property) and the pulsation suppressing property.
Therefore, it is a conventional practice to use the fuel hose in combination with a damping component such as a pulsation damper (P/D) or to elongate the overall fuel hose for the suppression of the pulsation.